Junction-box.



No. 857,053. iiTBNTED JUNE 18, 1907. B. T. GRBENPIBLD.

JUNCTION BOX.

APPLICATION rmnn mm: 11, 1906.

VII/III a i t lmm WITNESSES: 'NVENTOR ATTORNEY UNITED STATES ATENT OFFIQE. EDWIN GREENFIELD, F KIAlliESHh, NEW YORK.

i iliunorlon sox.

To all whom it may concern:

Beit known that I, EDWIN T. OREENFIELD, a citizen of the United States, residing at Kiamesha, in the county of Sullivanand junction boxes of the type commonly em-' ployed in installing electric lighting appliances in a building, and to which the conduc tors carrying the currentare run for connection to the wires of a fixture.

. More articularly, my improvements. re late to t e means whereby the conductors entering the box are held relatively thereto so that though they are sub'ected to considerable strain the will not e pulled free of the box. Junction boxes of this type have been heretofore rovided with clam ing devices for the com .uctors entering thc hox but in these boxes either the clamping devices have been arranged in inconvenient positions or the operation of those devices has involved considerable diiii ulty.

My invention contemplates disposing the clamping device in the most convenient position and providing an operating means therefor which-can bereadily actuated when the box is mounted in position. i

In accordance with my invention I mount the clamping device on the outer side of a wall of thobox and so arrange'the o erati ng means therefor that it can be readi y operatedirom within the box or on the other side of the wall on which the clam is mounted.

.1 have illustrated the pre'errcd embodi ment of my invention in the accompanying v drawings in which Figure 1 is a top view of the box, Fig'. 2 is I a section on line 22 of Fig. 1 and Fig. 3 is a section on line 33 of Fig. l. i

In these drawingsthe box.illustratcd'is of circular form and thezronductors enter through the rearwall, it being adapted more arti'cularly for use'as a ceiling box, but the Features of my invention are of e ual utility in one which is specially designer for uso'as a wall box' in which case it may be of rectangular form and the conductors may enter through the side walls. The box has a r lindrical side wall A and a rear wall B wh'idlr latter is provided with a central 0 )ening. An integral tubular portion 6 depenr s from Specification of Letters latent.

Application filed June 11,1905. Serial No- 321,186.

Patented June 18, 1907.

dinal ridgesb and on this side of each opening an upwardly extending lip 5'' ma be provided. Lying upon the rear wall of the box is a circular plate 0 confined in position in any suitable manner. The box may have a circular flange c withln wluch the plate '0 lies and this wall may have one or more projections. 0' turned over to hold the plate against dropping out. Or, the. plate may have slots 0 therein and screws c may extend therethrough and into the wall B. The U plate O has a central opening' out theret'hrough so as not to obstruct the' central opening through the box for the endof the fixture and around this opening are anumber of openings correspondin to the number of chambers 6 On one si e ofeach' of these openings, teeth at are formed on plate 0,

those being on the side of the openings away from the ridges bi. Between two of the chambers b a threaded opening is rovided,

in the rear wall B to receive ascrew .This

screwhas a conical end a. .In .thefplat'e C is an opening into which the end 0 screw E may enter. As thus constructed, the screw E may be withdrawn somewhat and the plate C moved around until the teeth (1 do not overlie the chambers b The bo'xand,

fixture may then be mounted in position in the usual manner and the conductors drawn into .and through the chambers I). These conductors are usually 'provided with an armoring of spirally formed strip and this-armoring may be removed from the end of each conductor back to such a point that its end will lie against the flange b, the insulated .wires themselves extending beyond this point for connection to the wires of the fixture. When the parts are in this relation, the screw Eis moved axially by-turning it with a screw driver and its conical end engages the wall of the opening in plate C. As the screw E is advanced more and more 'th plate is turned. on its axis by coaction with the conical end e of screw E, the plate being and means for moving said pla-teoperated guided by the Wall 0 and screws c until the teeth cl thereof are brought into hard engagement with the conductor or conductors, as shown in Fig. 1. The conductors aret-hus gripped tightly between the teeth (1 and the ridges b and are'held so firmly that they will.

the box is secured in an opening in a ceiling,-

the workman may properly position the conductors and other parts and when all are correct ly arranged he may operate the clampingdeviee from below to grip the conductors.

Having described my invention what I claim as new and desire to secure by Letters Patent is:

1. A junction box having a rotatable clamping device su ported on one side of a wall of the box an means for rotatingsa-id device from the other side of said wall, substantially as described.

. 2. A junction box having a clam ing device supported on one side of a wal ol" the box and rotatable relatively thereto, guides for said device, and means for rotating said device from the other side of said wall, substantially as described.

.3. A junction box having a clamping plate supported on one side of a wall of the box, sai plate having openings therein, teeth formed on aside of each of said-openings,

' fromthe opposite side of said wall, substantially as described. I

4. A junction box having a clamping plate supported on one side of a wall of the .box, said plate having openings therein, guides for said plate, teeth formed on a sideof each of said openings, and means for moving said plate operated from the opposite side of said wall, substantially as described.

5 A junction box having openings through a wall thereof for conductors, a plate supported on said wall and having corrpspond mg openings therethrough, means for retain-.

'ing said plate in position permitting predestances termined movement thereof relatively to said -wall, and means for moving said plate operated from the opposite side of said Well, substantially as described.

6. A. j unction box having openings through a wall thereof for conductors, a clamping device having corresponding openings therethrough supported upon one side of awall of the box, and means operated from the other side of said wall for causing saidclamping device to grip a conductor passing through said openings, substantially as described.

7. A junction box having a clamping plate supported upon a wall thereof, said plate having an opening therein and a screw-located in an opening in said wall and having a head at one end and at the'other an inclined portion adapted to enter said opening, substantially as described.

8. A junction box having side and rear walls and openings in said rear wall, a clamping plate having corresponding openings sup-.- ported on said rear wall, teeth formed on saidplate at one side of each of said openings and a screw passingthrough said rear wall and havingan inclined portion adapted to engage the wall of an opening in said plate to move the latter relatively to said wall, substan-' tially as described.

9. A junction box having openings in a I wall thereof, a clamping device having corresponding openings therethrough mounted for rotation on one side of a wall of the box, and means operated from the other side of said wall for rotating said clamping device and causing the same to grip a conductor passing through said openings, substantially as described.

10. A junction box having openlngs ffor conductors therein, a clamping device having corresponding openings therein supported on a wall of said box and means for rotating .95 said device and causing the same to grip conl ductors passing through said openings, substantially as described.

This specification signed and witnessed this 8th day of June, 1906.

EDWIN T. GREENFIELD. YVitnesscs:

WiLLLuu 'l. RUE-TE, Cnxs. E..W1Lso:\*. 

